The present invention relates to a disk drive unit, more precisely relates to a disk drive unit, which is capable of preventing vibration of magnetic heads and magnetic disks, which are caused by air steam.
FIG. 16 shows a plan view of an inner mechanism of a conventional disk drive unit. Magnetic disks 102 are accommodated in an enclosure 100. Arms 104 are swung parallel to surfaces of the disks 102 by actuators 106. Suspensions 108 are respectively fixed to front ends of the arms 104. A magnetic head 110 is attached to a front end of each suspension 108. The magnetic heads 114 respectively face the surfaces of the disk 102.
FIG. 17 is a side sectional view of the disk drive unit, in which the magnetic disks 102 are seen from the side. The disks 102 are arranged in an axial direction of a shaft 112. The magnetic heads 102 respectively correspond to the disks 102. The shaft 112 is connected to a spindle motor (not shown), so that the disks 102 are rotated together with the shaft 112 by the spindle motor.
While the disks 102 are stopped, the magnetic heads 110 respectively contact the surfaces of the disks 102; while the disks 102 are rotated, the magnetic heads 110 are lifted or floated from the surface of the disks 102 by air streams, which are caused by the rotation of the disks 102. For writing and reading data, seeking action of the magnetic heads 110 are executed by swinging the arms 106 about a shaft 105 by the actuators 106.
The disks 102 are rotated at high speed so as to write and read data, so dusts in the enclosure 100 badly influence the seeking action. Therefore, the enclosure 100 includes a filter so as to prevent invasion of dusts. Since the enclosure 100 is tightly sealed and the arms 104, the magnetic heads 110, etc. are moved at high speed, the air streams, which are caused by the rotation of the disks 102, are disturbed in the enclosure 100. Namely, stable air streams cannot be gained.
The magnetic heads 110 are vibrated by disturbed air streams or turbulent air streams, so that, in some cases, the magnetic heads 110 are excessively floated from the surface of the disks 102. With this action, the conventional disk drive unit has following disadvantages: the magnetic heads 110 cannot write and read data; the surfaces of the disks 102 are damaged by colliding the magnetic heads 110 therewith; the suspensions 108 are bent; and the magnetic heads 110 are damaged.
These days the seeking action must be faster and faster due to higher record density and greater memory capacity. Further, floating level of the magnetic heads 110, which are height of the magnetic heads 110 from the surface of the disks 102, must be precisely controlled, so that the vibration of the magnetic heads 110, which are caused by the turbulent air streams in the enclosure 100, must be prevented.
To protect the magnetic heads 110 from the turbulent air streams, another conventional disk drive unit has a screen member 120, which encloses the disks 102 (see FIG. 18). In this disk drive unit, a space between a side face of the screen member 120 and outer circumferential faces of the disks 102 is made narrow so as to limit air streams between the disks 102. With this structure, the vibration of the magnetic heads 110 can be reduced. However, the screen member 120 shown in FIG. 18 cannot fully prevent the vibration of the magnetic heads 110.
An object of the present invention is to provide a reliable disk drive unit capable of fully preventing vibration of magnetic heads, which are caused by turbulent air streams, which is caused by rotation of disks.
Another object of the present invention is to provide a disk drive unit capable of having higher record density and operating at higher speed.
To achieve the object, a first basic structure of the disk drive unit of the present invention comprises: an enclosure; a shaft being provided in the enclosure, the shaft rotatably holding a disk; and a screen member being provided on an inner face of the enclosure, the screen member enclosing the shaft and being extended in parallel to the shaft, wherein a space is formed between the screen member and an inner bottom face of the enclosure.
In the disk drive unit, another space may be formed between the screen member and the inner face of the enclosure. With this structure, the air streams caused by the rotation of the disk can be introduce into another space, so that the air streams, which upwardly flow in the enclosure, can be properly restricted. Further, the screen member may be continuously rounded along the inner face of the enclosure. With this structure, the air streams can be circulated in another space and the air streams, which upwardly flow, can be properly restricted.
A second basic structure of the disk drive unit of the present invention comprises: an enclosure; a shaft being provided in the enclosure; and a plurality of disks being provided in the enclosure and rotatably held, with regular separations, by the shaft, wherein diameter of one of the disks is greater than that of others.
The disk drive unit may further comprise a screen member being provided close to outer circumferential faces of the disks other than the disk having greater diameter and extended in parallel to the shaft.
Further, in the disk drive unit, a space may be formed between the screen member and an inner face of the enclosure.
In the disk drive unit of the present invention, the air streams, which upwardly flow from the inner bottom face when the disk is rotated, can be properly restricted. By restricting the air streams, the vibration of the magnetic disk and the magnetic head, which occur while rotating the magnetic disk, can be effectively restricted. Therefore, data can be precisely written and read with high speed rotation of the disk. Further, colliding the magnetic head with the surface of the disk can be prevented, so that crush of the magnetic disk can be prevented and reliability of the disk drive unit can be improved.